The present invention relates generally to an improved lettering apparatus or type composing system, and more particularly, to an improved lettering apparatus or type composing system adapted for use with a replaceable tape supply cartridge for supplying lettering tape into alignment with a lettering station embodied within the apparatus.
The lettering apparatus of the present invention is of the type which includes a means for generating a lettering force at the lettering station, a means cooperating with advancement means within the tape supply cartridge for advancing the tape toward alignment at the lettering station and means commonly in the form of a rotatable font for providing a character to be lettered at the lettering station. It is contemplated that the apparatus of the present invention can be used in a lettering operation in which the cartridge contains a supply of image carrying tape and color carrying ribbon and in which an image of a raised character is transferred from the ribbon to the tape as a result of the exertion of the lettering force. It is also contemplated, however, that the apparatus of the present invention can be used with a system in which the tape includes a thin layer of adhesive-backed material from which the character in alignment with the lettering station is cut and then ultimately removed for placement onto the desired medium. It is contemplated that this latter procedure can be utilized either with or without a supply of protecting ribbon disposed between the tape and the character.
Several lettering systems of the general type described above are currently available. For example, one of these is described in U.S. Pat. No. 4,243,333 and is directed to an improved means for creating a printing force. Specifically, this means includes a plurality of link members and a roller for causing pivotal movement of a print bar to generate the printing force. This print generation means is disposed in a plane generally perpendicular to the plane in which the tape supply cartridge is disposed. Another example of a prior art lettering apparatus of this type is described in U.S. Pat. No. 4,402,619. Similar to the device described in U.S. Pat. No. 4,243,333, this device also includes a printing force generating means which comprises a plurality of link members which cause the pivoting of a print bar with respect to a frame of the apparatus. In this device, the printing force generating means is also disposed in a plane generally perpendicular to the plane of the tape supply cartridge.
Although the above referenced prior art lettering systems and others have functioned satisfactorily in various applications and for various purposes, there continue to be ways in which such apparatus can be improved. For example, the force generating mechanism can be improved so that it is more efficient, compact and responsive to the needs of the system. Further, improved features are needed for letter spacing, for aligning and advancing the tape and for properly positioning the rotatable font. Accordingly, there is a need in the art for a lettering apparatus which embodies such improved features.